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    <div class="refentry" id="glDrawElementsInstanced">
      <div class="titlepage"/>
      <div class="refnamediv">
        <h2>Name</h2>
        <p>glDrawElementsInstanced — draw multiple instances of a set of elements</p>
      </div>
      <div class="refsynopsisdiv">
        <h2>C Specification</h2>
        <div class="funcsynopsis">
          <table style="border: 0; cellspacing: 0; cellpadding: 0;" class="funcprototype-table">
            <tr>
              <td>
                <code class="funcdef">void <strong class="fsfunc">glDrawElementsInstanced</strong>(</code>
              </td>
              <td>GLenum <var class="pdparam">mode</var>, </td>
            </tr>
            <tr>
              <td> </td>
              <td>GLsizei <var class="pdparam">count</var>, </td>
            </tr>
            <tr>
              <td> </td>
              <td>GLenum <var class="pdparam">type</var>, </td>
            </tr>
            <tr>
              <td> </td>
              <td>const void * <var class="pdparam">indices</var>, </td>
            </tr>
            <tr>
              <td> </td>
              <td>GLsizei <var class="pdparam">primcount</var><code>)</code>;</td>
            </tr>
          </table>
          <div class="funcprototype-spacer"> </div>
        </div>
      </div>
      <div class="refsect1" id="parameters">
        <h2>Parameters</h2>
        <div class="variablelist">
          <dl class="variablelist">
            <dt>
              <span class="term">
                <em class="parameter">
                  <code>mode</code>
                </em>
              </span>
            </dt>
            <dd>
              <p>
                    Specifies what kind of primitives to render.
                    Symbolic constants
                    <code class="constant">GL_POINTS</code>,
                    <code class="constant">GL_LINE_STRIP</code>,
                    <code class="constant">GL_LINE_LOOP</code>,
                    <code class="constant">GL_LINES</code>,
                    <code class="constant">GL_TRIANGLE_STRIP</code>,
                    <code class="constant">GL_TRIANGLE_FAN</code> and
                    <code class="constant">GL_TRIANGLES</code>
                    are accepted.
                </p>
            </dd>
            <dt>
              <span class="term">
                <em class="parameter">
                  <code>count</code>
                </em>
              </span>
            </dt>
            <dd>
              <p>
                    Specifies the number of elements to be rendered.
                </p>
            </dd>
            <dt>
              <span class="term">
                <em class="parameter">
                  <code>type</code>
                </em>
              </span>
            </dt>
            <dd>
              <p>
                    Specifies the type of the values in <em class="parameter"><code>indices</code></em>. Must be one of <code class="constant">GL_UNSIGNED_BYTE</code>,
                    <code class="constant">GL_UNSIGNED_SHORT</code>, or <code class="constant">GL_UNSIGNED_INT</code>.
                </p>
            </dd>
            <dt>
              <span class="term">
                <em class="parameter">
                  <code>indices</code>
                </em>
              </span>
            </dt>
            <dd>
              <p>
                    Specifies a byte offset (cast to a pointer type) into the buffer bound to <code class="constant">GL_ELEMENT_ARRAY_BUFFER</code>
                    to start reading indices from. If no buffer is bound, specifies a pointer to the location where the indices are stored.
                </p>
            </dd>
            <dt>
              <span class="term">
                <em class="parameter">
                  <code>primcount</code>
                </em>
              </span>
            </dt>
            <dd>
              <p>
                    Specifies the number of instances of the specified range of indices to be rendered.
                </p>
            </dd>
          </dl>
        </div>
      </div>
      <div class="refsect1" id="description">
        <h2>Description</h2>
        <p>
            <code class="function">glDrawElementsInstanced</code> behaves identically to <a class="citerefentry" href="glDrawElements.xhtml"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>
            except that <em class="parameter"><code>primcount</code></em> instances of the set of elements are executed. Those attributes
                        that have divisor N where N is other than zero
                        (as specified by <a class="citerefentry" href="glVertexAttribDivisor.xhtml"><span class="citerefentry"><span class="refentrytitle">glVertexAttribDivisor</span></span></a>)
                        advance once every N instances. Thus, the element transferred from instanced
                        vertex attributes is given by:
            </p>
        <div class="informalequation">
          <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                                        <mml:mfrac>
                                                <mml:mi mathvariant="italic">instance</mml:mi>
                                                <mml:mn>divisor</mml:mn>
                                        </mml:mfrac>
                </mml:mrow>
            </mml:math>
        </div>
        <p>

                        The value of <em class="parameter"><code>instance</code></em> may be read by a vertex shader as <code class="constant">gl_InstanceID</code>.
        </p>
        <p>
                        To enable and disable a generic vertex attribute array, call
                        <a class="citerefentry" href="glEnableVertexAttribArray.xhtml"><span class="citerefentry"><span class="refentrytitle">glEnableVertexAttribArray</span></span></a> and
                        <a class="citerefentry" href="glDisableVertexAttribArray.xhtml"><span class="citerefentry"><span class="refentrytitle">glDisableVertexAttribArray</span></span></a>.
        </p>
        <p>
                        If an array corresponding to a generic attribute required by a vertex shader
                        is not enabled, then the corresponding element is taken from the current generic
                        attribute state.
        </p>
      </div>
      <div class="refsect1" id="errors">
        <h2>Errors</h2>
        <p>
            <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>mode</code></em> is not one of <code class="constant">GL_POINTS</code>,
            <code class="constant">GL_LINE_STRIP</code>, <code class="constant">GL_LINE_LOOP</code>, <code class="constant">GL_LINES</code>,
            <code class="constant">GL_TRIANGLE_STRIP</code>, <code class="constant">GL_TRIANGLE_FAN</code>, or <code class="constant">GL_TRIANGLES</code>.
        </p>
        <p>
            <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>count</code></em> or <em class="parameter"><code>primcount</code></em> are negative.
        </p>
        <p>
            <code class="constant">GL_INVALID_OPERATION</code> is generated if a non-zero buffer object name is bound to an
            enabled array and the buffer object's data store is currently mapped.
        </p>
        <p>
                        <code class="constant">GL_INVALID_FRAMEBUFFER_OPERATION</code> is generated if the currently bound framebuffer is not
                        framebuffer complete (i.e. the return value from
                        <a class="citerefentry" href="glCheckFramebufferStatus.xhtml"><span class="citerefentry"><span class="refentrytitle">glCheckFramebufferStatus</span></span></a> is not <code class="constant">GL_FRAMEBUFFER_COMPLETE</code>).
        </p>
        <p>
            <code class="constant">GL_INVALID_OPERATION</code> is generated if transform feedback is active and not paused.
        </p>
      </div>
      <div class="refsect1" id="versions">
        <h2>API Version Support</h2>
        <div class="informaltable">
          <table style="border-collapse: collapse; border-top: 2px solid ; border-bottom: 2px solid ; border-left: 2px solid ; border-right: 2px solid ; ">
            <colgroup>
              <col style="text-align: left; "/>
              <col style="text-align: center; " class="firstvers"/>
              <col style="text-align: center; " class="lastvers"/>
            </colgroup>
            <thead>
              <tr>
                <th style="text-align: left; border-right: 2px solid ; ">
                 
            </th>
                <th style="text-align: center; border-bottom: 2px solid ; " colspan="2">
                <span class="bold"><strong>OpenGL ES API Version</strong></span>
            </th>
              </tr>
              <tr>
                <th style="text-align: left; border-right: 2px solid ; border-bottom: 2px solid ; ">
                <span class="bold"><strong>Function Name</strong></span>
            </th>
                <th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">
                <span class="bold"><strong>2.0</strong></span>
            </th>
                <th style="text-align: center; border-bottom: 2px solid ; ">
                <span class="bold"><strong>3.0</strong></span>
            </th>
              </tr>
            </thead>
            <tbody>
              <tr>
                <td style="text-align: left; border-right: 2px solid ; ">glDrawElementsInstanced</td>
                <td style="text-align: center; border-right: 2px solid ; ">-</td>
                <td style="text-align: center; ">✔</td>
              </tr>
            </tbody>
          </table>
        </div>
      </div>
      <div class="refsect1" id="seealso">
        <h2>See Also</h2>
        <p>
            <a class="citerefentry" href="glCheckFramebufferStatus.xhtml"><span class="citerefentry"><span class="refentrytitle">glCheckFramebufferStatus</span></span></a>,
                        <a class="citerefentry" href="glDisableVertexAttribArray.xhtml"><span class="citerefentry"><span class="refentrytitle">glDisableVertexAttribArray</span></span></a>,
            <a class="citerefentry" href="glDrawElements.xhtml"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>,
            <a class="citerefentry" href="glDrawArrays.xhtml"><span class="citerefentry"><span class="refentrytitle">glDrawArrays</span></span></a>,
            <a class="citerefentry" href="glDrawArraysInstanced.xhtml"><span class="citerefentry"><span class="refentrytitle">glDrawArraysInstanced</span></span></a>,
            <a class="citerefentry" href="glDrawRangeElements.xhtml"><span class="citerefentry"><span class="refentrytitle">glDrawRangeElements</span></span></a>,
                        <a class="citerefentry" href="glEnableVertexAttribArray.xhtml"><span class="citerefentry"><span class="refentrytitle">glEnableVertexAttribArray</span></span></a>,
                        <a class="citerefentry" href="glVertexAttribDivisor.xhtml"><span class="citerefentry"><span class="refentrytitle">glVertexAttribDivisor</span></span></a>
        </p>
      </div>
      <div class="refsect1" id="Copyright">
        <h2>Copyright</h2>
        <p>
            Copyright <span class="trademark"/>© 2010-2014 Khronos Group.
            This material may be distributed subject to the terms and conditions set forth in
            the Open Publication License, v 1.0, 8 June 1999.
            <a class="link" href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>.
        </p>
      </div>
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